. of course,presidentobamaspentnearly four hours there today, as partf interface service that they had, michelle. >> scott cohn is in boston. he has the latest from there, scott. >> michelle, we are going to finally get an official briefing from law enforcement, as bill said, that will come roughly around the top of the hour. and the plan is that it will be all law enforcement. the previous briefings have included the governor and the mayor. this is now sort of getting down to business, and it is widely anticipated that we will probably see some pictures of people of interest, that they captured on video at the time of the explosions on monday afternoon. that's part of the whole process of healing this city, healing our city was the theme of the remembrances today in boston, culminating in an hour and 15-minute long memorial service, interfaith service, at the cathedral of the holy cross. president obama speaking and delivering a message of renewal. >> this time next year, on the third monday in april, the world will return to this great american city, to run harder than ever and to ch